Unit collision refers to the mechanic by which two units cannot occupy the same region in a game of League of Legends. Units affected by this include champions, minions, and monsters. Some champions have abilities that allow them to ignore unit collision.
Ignoring unit collision
Champion abilities
Alistar's 
Trample - for 3 seconds after casting an ability
Braum's 
Unbreakable - while active
- Evelynn's Dark Frenzy - while active. And while stealthed.
- Fizz's Nimble Fighter - persistent
- Garen's Judgment - while active
- Hecarim's Devastating Charge - while active
- Janna's Zephyr - when not on cooldown
- Jayce's Hextech Capacitor - for 1.25 seconds after casting Transform
- Kassadin's Void Stone - persistent
- Kennen's Lightning Rush - while active
- - while active
- Nocturne's Duskbringer - while on trail
- Rek'Sai's Burrow - while active
- Udyr's Bear Stance - while active
- Zed's Death Mark - while active
